Very much the helpful information for me, thanks.

Hi everyone,

I have reviewed this thread over and over for the last couple months while I tried to tackle the problem on my HP DV4170us laptop. I wanted to share my experiences so hopefully they can help some of you.

For me, this was an intermittent problem until one day it was permanent. The USB ports were working fine, then they started acting up, and finally one day, just quit working all together. I tried just about everything imaginable in terms of a SW fix from virus scans to many things posted on this forum. I never performed an OS restore because I did not believe that was the problem at all.

My solution: I purchased a new motherboard on eBay for $75 and swapped mine out. This completely fixed my problem!

I am not sure at this time of HOW the USB ports on the motherboard went bad. Connected to my laptop are two external hard drives, optical mouse, and an M-audio FastTrack recording interface. It may have had something to do with the M-audio device, but I am not certain. I never liked the fact that the unit was USB powered. I have since purchased a powered USB hub so that it will have a separate power supply.

I am wondering, how many of you with the USB problem have experienced other problems as well. I am particularly interested in the people who have had luck simply taking out the battery for 30 mins. For myself, I had also noticed intermittent keyboard functionality, problems shutting down the computer, and battery charging. Lastly, when my computer first boots, the screen had a red/pink tint to it until the windows XP logo appears and then the colors were normal. Many of these problems lead me to think it is a power issue. Has anyone simply tried replacing the AC adapter and/or battery? Even though my computer is working again, my battery still doesn't charge. I would like to determine if this issue is related or not.

Best of luck to you all.

I have a possible workaround to try and it worked. I am running Vista 32bit, but the problem sounds essentially the same. The workaround is simple. Disconnect all usb devices. Then you must disconnect power to your computer for around 10-30 seconds thereby erasing any volatile memory on the MB. Reconnect, now reboot. After I did this the usb devices were all recognized like normal.
Here's some suggestions that did not work. Reformatting your HDD and reinstall OS. REinstalling USB controller drivers. Replacing the MB. Sending it off to be repaired. Putting in a new usb card. Doing all those trick with the registry. While I don't know the actual cause of the problem it seems it may be do to a conflict with the OS Device Manager and the hardware(USB controller). After you have it working, don't just yank out usb devices. Choose the remove hardware safely icon in system tray and actually stop the device before removing. This will likely prevent re-corrupting device drivers. Anyway, Hope it helps.

Have to be very careful about unplugging one device and then plugging in another. I fixed the problem of the unregonized device by shutting everything down and then disconnecting the power supply and then restarting - plugging the device in I wanted to use - my camera - then turning the device on and it recognized it _FINALLY_ and then I safetly removed the hardware properly and then I plugged in my Printer and then turned the printer on and then it recognized it too...I'm flying now.

Sometimes the USB ports build a static charge and malfunction. By disconnecting the power supply (when the system is shut down), hold the power button on the case down for about 10 seconds,release, then reconnect the power and start the system.

Folks usually recommend using the USB ports on the back of the case. This is recommended as there are a lot of systems out there that still have USB 1 ports on the front of the case and USB 2 ports on the back. The latter support newer hardware build to run on USB 2 ports.

The other situation is where one installs a new piece of hardware, say a printer, without un-installing the old printer drivers. The old printer drivers attempt to load and the USB connection fails, due to the old printer driver conflict.

And yes, switching out hardware on different ports also confuse Windows. Try to plug in your hardware into the same USB port each time.

I had a similar problem on a ~2-year-old Alienware desktop running WinXP Pro: most USB devices were working fine, but the WiFi adapter spontaneously started dropping the connection. When I tried to reset it, it seemed to become incompatible with the mouse-- that is, the mouse cursor would freeze when the WiFi was plugged in. I worked that problem a bit using some of the techniques described above in this thread, and pretty soon Windows simply refused to recognize the adapter at all, or even another one like it, even though I had tested both successfully on another machine.

Anyway, I grew fed up and decided to assume the problem was the USB hardware. I bought new 4-port USB PCI card for about $8 via Amazon. Problem solved in record time.

There are lots of cheap USB cards:
http://www.amazon.com/s/ref=nb_ss?url=search-alias%3Daps&field-keywords=usb+pci

Not much help to notebook users, I know, but if you have a PCMCIA slot, you could buy a card for that:
http://www.amazon.com/s/ref=nb_ss?url=search-alias%3Daps&field-keywords=usb+pcmcia

My solution was so cheap that I didn't mind giving it a shot even if the problem turned out to be OS- or driver-related. Maybe it was. But now it's working, and I'm happy.

I have a same problem but i resolved it by shut down my PC, unplug everything, do not forget unplug battery too. i think most people forget unplug the battery and then this method does not work for them. Remember unplug everything.

Did not work for me. But i figure it out eventually.

In my pc is a card reader who is messing with my USB hubs. If it is enabled, non of the hubs is working, constant DEVICE not recognized balloon is popping. When i disable it all of the hubs instant start to work properly.

I have been messing around with a belkin mouse that stopped working just after I decided to do the vista update for my Toshiba laptop A215-S4757 I have only had problems with my Belkin mouse every other product hooked to my laptop is made by a company that Microsoft recognizes. I have installed a Belkin wireless card before and got a message not a Microsoft compatible product but it worked anyway. Finally I got a chance to borrow a microsoft mouse and I had been playing around switching ports to get the USB mouse working again for half the day. The computer immediately recognized the Microsoft usb mouse and installed drivers for it.

I am not saying some people don't have actual hardware issues.
I am only posing the question how many of your problems started after and update and how many have products microsoft may not wish to take the time to make sure their software works properly with.
my usb extras
A t-mobile dash that came with with a microsft install disk.
A seagate 40gb removable hard.
for some time I thought it was the dash conflicting with the mouse, but why did the drivers install right away for the micro soft mouse and not even installing belkin drivers helped the belkin work. you tell me.